One of my favorite Lovecraft tales is "The Mound" by H.P. Lovecraft and Zealia Bishop in which the underground world of K'n-Yan is described. I was disappointed when FFG didn't include K'n-Yan as an Other World (though there is a picture of it in The Art of H.P. Lovecraft's Cthulhu Mythos ) so here it is, along with 4 custom gate cards:
